In his fifth lecture on the Steipler for Torah in Motion, professor Marc B. Shapiro says: “In the last ten years, upsherin (party to cut for the first time a three year old boy’s hair) has become popular in the Modern Orthodox world.”
“In my town, every year I’ll hear of two or three. Many of these people will say that they come from hasidic stock. Years ago, just because you were from hasidic stock, no one would do this.”
“It’s a good chance for a party. It’s fun. You get to cut the kid’s hair. The Modern Orthodox are always in for a party. Invite the Modern Orthodox to come in for some serious learning, that’s hard. But invite them for good food, they’re usually up to. Modern Orthodoxy is to a large extent a lifestyle as opposed to an ideological decision.”
According to Wikipedia: “Upsherin or Upsherinish (Yiddish: אפשערן, lit. “shear off”) is a Jewish haircutting ceremony, kabbalistic in origin, held when a Jewish boy is three years old. It is also known as “chalaka”, written חלאקה, from the Arabic word حلاقة.”